what the definition of age range in earth science?

I'm doing research but I can still not find it.

Geologic time scale?

http://www.mcz.harvard.edu/Departments/InvertPaleo/Trenton/Intro/GeologyPage/Geologic%20Setting/geologictime.htm

In Earth science, the term "age range" typically refers to the span of time over which a particular event, process, or phenomenon occurred. It describes the duration or timeframe within which a geological event or process took place.

To determine the age range in Earth science, various dating techniques are employed depending on the specific timeframe being investigated. Here are a few common methods:

1. Relative Dating: This technique involves determining the age of rocks, fossils, and geological formations relative to one another. It focuses on establishing the sequence of events without assigning specific numerical ages. Relative dating methods include the Law of Superposition, which states that younger rocks are found above older rocks, and the principle of cross-cutting relationships, which states that a geological feature must be younger than any feature it cuts across.

2. Absolute Dating: Also known as radiometric dating, this approach involves measuring the ratios of certain isotopes (atoms of the same element with different numbers of neutrons) in rocks or fossils to determine their absolute ages. Radiometric methods, such as carbon-14 dating or uranium-lead dating, rely on the known rates of radioactive decay of isotopes to estimate the age range of a sample.

3. Stratigraphy: This method utilizes the study of layers (strata) of rocks and sedimentary deposits to determine relative ages. By examining the sequence, thickness, and composition of these layers, geologists can infer the approximate age of the materials.

4. Fossil Dating: Fossils provide critical clues for dating rocks and understanding Earth's history. Paleontologists analyze the fossil record to determine the age range of the sedimentary layers where fossils are found. Fossils of known age can be used as "index fossils" to correlate rock layers across different locations.

It's important to note that different dating techniques are applicable to different age ranges. For instance, radiocarbon dating is suitable for relatively recent materials (up to about 50,000 years), while other techniques, like uranium-lead dating, are used to determine the ages of much older rocks (up to billions of years).